Obesity refers a state of a body that over-accumulates body fat which causes negative effects on health, which could cause shorter life expectancy and various health problems. According to the definition of obese by World Health Organization (WHO), individuals with the body mass index (BMI) greater than 25 are overweight and individuals with BMI greater than 30 are obesity. Some East Asian nations adopt more rigorous standards, e.g. the Ministry of Health and Welfare of Taiwan declared in April, 2002 that Taiwanese adults with BMI 27 are obese, or with 24≤BMI<27 are overweight.
Statistical data shows the population of overweight and obesity around the world is over 2.7 billion in 2014, wherein approximately 13% population were obese. The chance of these obese people who might suffer from related diseases such as, cardiovascular diseases, hyperlipidemia, diabetes, and cancers are drastically increased than average people. A research report of the WHO also indicated that among the diseases which caused risks of mortality around the world, overweight and obesity ranked 6th. Research data indicates that at least more than 3.4 million adults died of chronic diseases caused by overweight or obesity in 2013, wherein the medical burdens of 44% of diabetes and 23% of ischemic heart disease are attributable to obesity. Furthermore, the age of obese people is in a gradually falling trend. According to WHO data, there are approximately more than 40 million children under the age of five are overweight worldwide in 2011. According to a report published by the Johns Hopkins University Bloomberg School of Public Health in 2007, indicating that approximately 75% of adults in the USA would be overweight, wherein 41% of the population thereof would be classified as obese in 2015. With the rising of developing countries, the global population of obesity will rapidly increase and become one of the major prevalent diseases. The Centers for Disease Control and Prevention (CDC) of the USA indicated that the population of obese adults in the USA is more than 72 million, and 40% of global obese population is in the Asia-Pacific region. The percentage of overweight and obese adults in China was drastically increased from 25% in 2002 to 38.5% in 2010; it predicts that, in 2015, 50% to 57% of the population in China will be overweight.
Obesity is a health problem highly concerned worldwide, and studies show that the causes of obesity are highly complex with multiple factors involved. More and more evidences also show that obesity is an internal metabolic disorder disease which is not a simple problem that can be improved by self-control, but a complex symptom related to internal appetite regulation and energy metabolism. Obesity not only increases mortality rate and causes huge medical burden, but also affects the quality of life to mankind. Though the cause of obesity is not completely identified, it is believed to be related to the factors of genetics, metabolism, biochemistry, culture, and spiritual-social. Research shows many causes of death are correlated with obesity including cancers, cardiovascular diseases, cerebrovascular diseases, diabetes, chronic lower respiratory diseases, chronic hepatic disease and liver cirrhosis, hypertensive diseases, renal disease, etc., indicating that the problem of obesity has become a highly concerned issue globally. In recent years, the prevalence of obesity has risen higher and higher, metabolic syndromes caused by metabolic abnormalities such as, high blood pressure (hypertension), high blood sugar (hyperglycemia), insulin resistance, and dyslipidemia, would accompanied by obesity, which would easily lead to diseases such as, diabetes, cardiovascular diseases, atherosclerosis, cerebrovascular disease, and cancer, which cause stroke, myocardial infarction, and even death.
The mechanisms of current synthetic drugs for losing weight can be divided into two categories, which are appetite suppression and blocking part of the intestinal absorption of dietary fat respectively. Among them, appetite suppression is the main mechanism of commercial weight loss drugs on the market in the past and nowadays. This type of drugs include Sibutramine (Reductil®), Lorcaserin, Qsymia®, and Contrave, etc, which have severe side effects and a certain degree of cardiovascular diseases risk. Taking the weight loss drug Sibutramine (Reductil®), which has been recalled from the market, for example, its market share was once as high as 70 percent; however, it was proved to increase the risks of causing cardiovascular disease. Therefore, the weight loss drugs containing Sibutramine ingredient were recalled from the markets of the EU, the United States, Australia, and Taiwan in 2010.
The weight loss drug which blocks part of the intestinal absorption of dietary fat is Orlistat; it is a specific and reversible gastrointestinal lipase inhibitor, by means of the inhibition of lipase secreted from pancreatic and intestine, the intestinal absorption of dietary fat is reduced by 25% to 30%. Due to the main mechanism of Orlistat is blocking fat absorption, gastrointestinal side effects such as oily stool, increased number of bowel movements, flatulence, etc. may occur during medication intake, and it would interfere with fat-soluble vitamin absorption; there are also some cases of severe side effects such as liver damage, and gallstones, etc., in foreign countries.
Therefore, the current synthetic drugs used for weight loss remain to have different degree of cardiovascular risks and safety concerns; the market demands a weight loss drug that is safer, with low side effects, without cardiovascular risk concerns, could effectively reduce weight and body fat, and could also reduce cardiovascular risk at the same time.
The document “Dietary Polyphenols and Obesity” published by Mohsen Meydani and others discloses that the total body weight gain of rat can be reduced through oral intake of curcumin. However, the oral intake dosage of curcumin disclosed in that document is high as 250 to 10000 mg/kg, and its effect on weight loss is limited.
Therefore, in the market, there is still a need for a weight reduction pharmaceutical composition which can effectively reduce body weight, with low dosage, low side-effects, and good safety. Under the high demand from both consumers and doctors, the development of weight reduction pharmaceutical composition to break through the limitation of current technologies shall be the problem need to be desperately discussed and solved.